Some further thoughts on my theory that the woman was a teenage runaway; if she DID run away, and she WAS reported missing...these girls were in the isotopes range.
http://www.charleyproject.org/cases/l/larosa_irene.html - 17, went missing from Ellington, CT, March 1971. Something I need to point out is that she simply walked out of her home and was only reported missing last year. Her age in 1981 would have been 27.
http://www.charleyproject.org/cases/k/kramer_janet.html - 13, missing from Willmar, MN, January 1st 1971. (Unsure if that is exact date) Very few details available. Her age in 1981 would have been 23.
http://www.charleyproject.org/cases/m/miller_jeanette.html - 17, missing from Arlington, WA, September 16th 1970. Very few details available. Her age in 1981 would have been 28.
http://www.charleyproject.org/cases/c/cole_rose.html - 15-16, missing from Oakland, CA, 1972 - 1973. Had supposedly run away from a cult. Her age in 1981 would have been 25.
http://www.charleyproject.org/cases/b/britten_niki.html - 16, missing from Albany, OR, 1969. Something I need to note is that when she called up her parents a few months after she vanished, she said she was in New York (not sure if she meant the city or the state) which is a lot closer to Allenstown than Albany. Her age in 1981 would have been 28.
http://www.charleyproject.org/cases/g/groenenberg_corinne.html - 14, missing from Modesto, CA, November 1st 1973. Had been seen getting into a blue or green truck with an unidentified driver and had definitely been hitchhiking. Her age in 1981 would have been 22, which puts her at the start of the age range, but maybe it's possible that the four were killed after 1981.
http://www.charleyproject.org/cases/m/mallon_kim.html - 13, missing from Los Angeles, CA, September 30th 1973. If I'm right, Evans visited Los Angeles. Her age in 1981 would have been 21, but as I said above, maybe the four were killed after 1981.
http://www.charleyproject.org/cases/p/pickle_sherry.html - 15, missing from Long Beach, CA, May 16th 1972. She may have been with a male companion or tried to hitchhike to Los Angeles. Very few details are available. Her age in 1981 would have been 25.
I also considered whether this woman may be the mother of the middle child.
https://www.findthemissing.org/en/cases/show/11802, Linda Miller, a Native American female from San Rafael, CA, went missing on or about July 1st 1973. She reportedly went to Guadalajara, Mexico, but never returned, only to be reported missing in 2001. And here's the clincher; she disappeared with a man named Cary Kristal, whom I can find nothing about. Doe Network states '
possibly' named Cary Kristal.